1. Field of the Invention
The present invention relates to a production managing system of semiconductor devices in which a production of semiconductor devices is managed by a remote user by using an information communication line such as an internet, etc.
2. Description of Related Art
The production management of semiconductor devices ordered by a user has been performed by a semiconductor device manufacturer by measuring parameters of the semiconductor devices in respective production process steps thereof along a production line and checking the measured parameters on whether or not the parameters are within predetermined specifications.
That is, for example, thickness of a thin film formed on a substrate is checked on whether or not its thickness is within a thickness specification thereof in the forming step of the thin film and a wiring pattern is checked on whether or not a width thereof is within a width specification of the wiring pattern in a wiring pattern forming step in which the wiring pattern is formed by etching the thin film through a photolithographic step.
However, a production management in these checks is to merely determine whether or not a result of check is acceptable.
Final yield of semiconductor device, that is, the number of semiconductor devices obtained finally as acceptable products, is confirmed by confirming electrical characteristics and operations of completed semiconductor devices, which are functionally acceptable, by using a semiconductor tester.
Therefore, it is usual that a user who ordered the semiconductor devices can not know the number of normal semiconductor devices, which are practically obtained, before the production of all of them is completed.
As mentioned above, since, in the conventional production management of semiconductor devices, it is impossible for the user to know the number of finally obtainable normal semiconductor devices in every process and to confirm the number of normal semiconductor devices having acceptable electric characteristics before the semiconductor devices are completed, the user can not know the number of normal products until the semiconductor devices are delivered to the user.
Therefore, if a result obtained in the check in every process can not be detected by usual check in the conventional production management, there may be a case where the number of completed products delivered to the user is smaller than the number of products ordered by the user.
Therefore, when the shortage of the number of normal products is confirmed after the number of normal products is confirmed, it is necessary for the user to throw in a lot (constituted with in unit of wafer or wafers) again for production of semiconductor devices the number of which corresponds to the shortage. However, the production of semiconductor devices of the newly thrown lot usually takes about two months from the throwing-in of the lot to a completion of the semiconductor devices. Therefore, in the case where the number of normal products is short due to abnormality of process, a production schedule thereof is delayed substantially.
The present invention was made under the circumstances and has an object to provide a production managing system of semiconductor devices, which is capable of estimating not only the quality of processing in every process step but also the number of finally obtainable normal semiconductor devices ordered by a user in every process step such as contact-hole forming step.
The production managing system according to the present invention is featured by comprising, in a semiconductor device producing center connected to at least one usr terminal through an information communication line, a plurality of production devices for performing production processes in respective process steps, a corresponding number of in-line measuring devices provided next to the respective production devices, for measuring process parameters corresponding to the respective process steps of the production devices and outputting results of the measurements in units of lot of semiconductor devices as measured data, a database storing, for each wafer group including one or more wafers, data of production method for producing semiconductor devices, the measured data, specifications of the process steps corresponding to the measured data, estimated yields, data of the date and hour of an input of the lot, data of the scheduled date on which each process step is performed, data of actual date of completion of every step and data of the scheduled date of completion of the semiconductor devices, correspondingly to lot number data of the semiconductor devices and a server including an estimated yield operating unit for calculating the estimated yield, which is a final yield, on the basis of the specifications and the measured data, and a production managing unit for performing a production management of semiconductor devices ordered by a user on the basis of the respective data inputted by the user and the estimated yields, wherein the server performs write and read of the respective data inputted from the user terminal with respect to the database.
In this production managing system, the production managing unit manages the production of semiconductor devices by producing process control tables for the respective wafer groups, each of which is composed of the data of scheduled date and hour of each of the process steps used for the lot management, on the basis of the production method data, the data of lot input date and hour and the data of scheduled date of completion and controlling the process steps of the respective lots on the basis of the process control tables.
In this production managing system, the estimated yield operating unit calculates the estimated final yield after the process steps of the lot is completed and the process parameters are measured on the basis of the specifications, on the basis of statistical values of the measured data, the specifications and old data.
In this production managing system, the user terminal outputs the specifications inputted by the user for respective process steps, data of measuring positions indicative of positions on the wafer to be measured and element data indicative of the kind of elements to be measured to the server together with the lot number and the, server writes the inputted specifications, the measuring position data and the element data, in regions of the semiconductor devices corresponding to the lot number data in the database.
In this production managing system, the user terminal outputs data of re-input date and re-inputted wafer number inputted by the user correspondingly to the estimated yield to the server and the server writes the scheduled process data for every step of the lot having the wafers corresponding to the re-inputted wafer number data, correspondingly to the production schedule based on the re-input date data and the re-inputted wafer number data.
In this production managing system, when the estimated yield estimated by the measurement result in every step is lower than a minimum yield assigned by the user, the production managing unit notifies the user terminal of the detection result.
In this production managing system, the in-line measuring devices irradiate through-holes, which are formed in an insulating film for electrical connection between wiring patterns laminated on both sides of the insulating film, with electron beam, measures electric current values flowing correspondingly to configurations of the through-holes and outputs the measured current values as the measured data.
In this production managing system, the estimated yield operation unit may calculate an estimated yield in every step on the basis of old data, calculate the number of normal products of every wafer group on the basis of the estimated yield and calculate an estimated cost of the semiconductor device on the basis of the number of normal products and the working ratio of the production devices.
A production managing method for semiconductor devices, according to the present invention, comprises the steps of inputting at least data of method for producing semiconductor devices, measured data, specifications of the process step corresponding to the measured data, data of lot input date and hour, data of scheduled process step date, data of actual date of completion in every step and data of scheduled date of completion of the semiconductor devices, all of which are inputted by a user through a user terminal for every wafer group including at least one wafer, storing the data of method for producing semiconductor devices, the measured data, the specifications of the step corresponding to the measured data, the data of lot input date and hour, the data of scheduled process step date, the data of actual date of completion in every step and the data of scheduled date of completion of the semiconductor devices in a database, performing process processing corresponding to the process steps performed sequentially in each of a plurality of production devices, measuring process parameters corresponding to process in every of the process steps, calculating an estimated yield, which is a final yield, in every wafer group on the basis of the measured parameter data and the specification in every step and storing these data for every wafer group in the database, wherein the production management of the semiconductor devices ordered by the user is performed on the basis of the respective data inputted by the user and the estimated yield.
A production managing program of the present invention, for performing a semiconductor production management by using the production managing system mentioned above, comprises the steps of inputting at least the data of method for producing semiconductor devices, the measured data, the specifications of the process step corresponding to the measured data, the data of lot input date and hour, the data of scheduled process step date, the data of actual date of completion in every step and data of scheduled date of completion of the semiconductor devices, all of which are inputted by the user through the user terminal for every wafer group including at least one wafer, storing the method data, the measured data, the specifications of the step corresponding to the measured data, the data of lot input date and hour, the data of scheduled process step date, the data of actual date of completion in every step and the data of scheduled date of completion of the semiconductor devices in the database, performing process processing corresponding to process steps performed sequentially in each of the production devices, measuring process parameters corresponding to process in every process step, calculating an estimated yield, which is a final yield, in every wafer group on the basis of the measured parameter data and the specification in every step and storing these data for every wafer group in the database, wherein the production management of the semiconductor devices ordered by the user is performed by a computer on the basis of the respective data inputted by the user and the estimated yield.